目的 了解铜离子转运蛋白1（copper transport protein 1,CTR1）在大鼠内耳的表达情况及硫酸铜和顺铂鼓室给药对CTR1表达的影响。方法 Wistar雄性大鼠24只,随机分为4组,每组6只,Ⅰ组为正常对照组（非处理组）;Ⅱ组为双耳圆窗龛放置顺铂...目的 了解铜离子转运蛋白1（copper transport protein 1,CTR1）在大鼠内耳的表达情况及硫酸铜和顺铂鼓室给药对CTR1表达的影响。方法 Wistar雄性大鼠24只,随机分为4组,每组6只,Ⅰ组为正常对照组（非处理组）;Ⅱ组为双耳圆窗龛放置顺铂溶液（0.5mg/ml）的明胶海绵;Ⅲ组为双耳圆窗龛放置顺铂溶液（1mg/ml）的明胶海绵;Ⅳ组双耳圆窗龛放置硫酸铜溶液（0.02mg/kg）的明胶海绵。采用免疫组织化学技术,对各组耳蜗冰冻切片行CTR1蛋白的免疫组织化学染色,光学显微镜下观察耳蜗组织中CTR1的表达情况;提取各组耳蜗组织总蛋白,应用Western-blot技术检测各组CTR1蛋白表达水平;提取耳蜗组织的总RNA,应用RT-PCR技术检测各组CTR1mRNA的表达水平。结果 Ⅰ-Ⅳ组大鼠的耳蜗各回Corti器、螺旋神经节、血管纹的细胞质和细胞膜上均有CTR1表达,CTR1的平均光密度值呈降低趋势;各组耳蜗组织均有明显的CTR1表达,Ⅰ-Ⅳ组CTR1蛋白的光密度值分别为0.532±0.031、0.394±0.024、0.234±0.030和0.191±0.015,呈下降趋势,各组间比较差异有统计学意义（P〈0.05）;各组耳蜗组织均有明显的CTR1mRNA表达,Ⅰ-Ⅳ组光密度值分别为0.508±0.035、0.391±0.022、0.240±0.023和0.186±0.021,呈下降趋势,各组间比较差异均有统计学意义（P〈0.05）。结论 CTR1在大鼠内耳有丰富的表达,其表达量可随鼓室内顺铂浓度增高而下降,且鼓室内给予硫酸酮其表达量下降。展开更多
Industrial activities such as smelting emissions,mineral combustion and industrial wastewater discharge might lead to copper pollution in the environment.This kind of copper pollution has harmful effects on aquatic o ...Industrial activities such as smelting emissions,mineral combustion and industrial wastewater discharge might lead to copper pollution in the environment.This kind of copper pollution has harmful effects on aquatic o rganisms,plants and animals through direct or indirect exposure.However,the current understanding of the toxicity of copper is rather limited.Copper overload can perturb intracellular homeostasis and induce oxidative stress and e ven cell death.Recently,cuproptosis has been identified as a copper-dependent form of cell death induced by o xidative stress in mitochondria.We uncover here that zinc transporter 1(ZNT1)is an important regulator involved in cuproptosis.Firstly,we established the copper overload-induced cell death model with the overexpression of copper importer SLC31A1 in HeLa cells.Using this model,we conducted unbiased genome-wide CRISPR-Cas9 screens in cells treated with copper.Our results revealed a significant enrichment of ZNT1 gene in both library A and library B plasmids.Knocking out of ZNT1 in HeLa cells notably prevented cuproptosis.Subsequent knockout of metal transcription factor 1(MTF1)in ZNT1-deficient cells nearly abolished their ability to resist copper-induced cell death.However,overexpression of metallothionein 1X(MT1X)in the double-knockout cells could p artially restored the resistance to cuproptosis by loss of MTF1.Mechanistically,knockout of ZNT1 could promote MT1X expression by activating MTF1.As a consequence,the interaction between MT1X and copper was e nhanced,reducing the flow of copper into mitochondria and eliminating mitochondria damage.Taken together,this study reveals the important role of ZNT1 in cuproptosis and shows MTF1-MT1X axis mediated resistance to c uproptosis.Moreover,our study will help to understand the regulatory mechanism of cellular and systemic copper homeostasis under copper overload,and present insights into novel treatments for damages caused by both genetic copper overload diseases and environmental copper contamination.展开更多
文摘目的 了解铜离子转运蛋白1（copper transport protein 1,CTR1）在大鼠内耳的表达情况及硫酸铜和顺铂鼓室给药对CTR1表达的影响。方法 Wistar雄性大鼠24只,随机分为4组,每组6只,Ⅰ组为正常对照组（非处理组）;Ⅱ组为双耳圆窗龛放置顺铂溶液（0.5mg/ml）的明胶海绵;Ⅲ组为双耳圆窗龛放置顺铂溶液（1mg/ml）的明胶海绵;Ⅳ组双耳圆窗龛放置硫酸铜溶液（0.02mg/kg）的明胶海绵。采用免疫组织化学技术,对各组耳蜗冰冻切片行CTR1蛋白的免疫组织化学染色,光学显微镜下观察耳蜗组织中CTR1的表达情况;提取各组耳蜗组织总蛋白,应用Western-blot技术检测各组CTR1蛋白表达水平;提取耳蜗组织的总RNA,应用RT-PCR技术检测各组CTR1mRNA的表达水平。结果 Ⅰ-Ⅳ组大鼠的耳蜗各回Corti器、螺旋神经节、血管纹的细胞质和细胞膜上均有CTR1表达,CTR1的平均光密度值呈降低趋势;各组耳蜗组织均有明显的CTR1表达,Ⅰ-Ⅳ组CTR1蛋白的光密度值分别为0.532±0.031、0.394±0.024、0.234±0.030和0.191±0.015,呈下降趋势,各组间比较差异有统计学意义（P〈0.05）;各组耳蜗组织均有明显的CTR1mRNA表达,Ⅰ-Ⅳ组光密度值分别为0.508±0.035、0.391±0.022、0.240±0.023和0.186±0.021,呈下降趋势,各组间比较差异均有统计学意义（P〈0.05）。结论 CTR1在大鼠内耳有丰富的表达,其表达量可随鼓室内顺铂浓度增高而下降,且鼓室内给予硫酸酮其表达量下降。
文摘Industrial activities such as smelting emissions,mineral combustion and industrial wastewater discharge might lead to copper pollution in the environment.This kind of copper pollution has harmful effects on aquatic o rganisms,plants and animals through direct or indirect exposure.However,the current understanding of the toxicity of copper is rather limited.Copper overload can perturb intracellular homeostasis and induce oxidative stress and e ven cell death.Recently,cuproptosis has been identified as a copper-dependent form of cell death induced by o xidative stress in mitochondria.We uncover here that zinc transporter 1(ZNT1)is an important regulator involved in cuproptosis.Firstly,we established the copper overload-induced cell death model with the overexpression of copper importer SLC31A1 in HeLa cells.Using this model,we conducted unbiased genome-wide CRISPR-Cas9 screens in cells treated with copper.Our results revealed a significant enrichment of ZNT1 gene in both library A and library B plasmids.Knocking out of ZNT1 in HeLa cells notably prevented cuproptosis.Subsequent knockout of metal transcription factor 1(MTF1)in ZNT1-deficient cells nearly abolished their ability to resist copper-induced cell death.However,overexpression of metallothionein 1X(MT1X)in the double-knockout cells could p artially restored the resistance to cuproptosis by loss of MTF1.Mechanistically,knockout of ZNT1 could promote MT1X expression by activating MTF1.As a consequence,the interaction between MT1X and copper was e nhanced,reducing the flow of copper into mitochondria and eliminating mitochondria damage.Taken together,this study reveals the important role of ZNT1 in cuproptosis and shows MTF1-MT1X axis mediated resistance to c uproptosis.Moreover,our study will help to understand the regulatory mechanism of cellular and systemic copper homeostasis under copper overload,and present insights into novel treatments for damages caused by both genetic copper overload diseases and environmental copper contamination.
